1. Technical Field
The present invention relates to a fluid supply device that supplies fluid from a main tank through a subtank to a fluid-discharging head, to a printing device, and to a method of cleaning a printing device.
2. Description of Related Art
One example of a fluid supply device is a device that is incorporated in a printer connected to a personal computer, for example, and supplies ink as the fluid to an inkjet recording head. Japanese Unexamined Patent Appl. Pub. JP-A-2001-270133, for example, teaches a fluid supply device that has a subtank unit, a pump, and a pump control means. The subtank unit is mounted on a carriage, receives ink that is supplied through an ink supply tube from an ink cartridge into a storage chamber, and supplies ink from the ink storage chamber to an inkjet recording head when printing. The pump supplies ink from the ink cartridge to the subtank unit. The pump control means controls the ink flow according to a drive signal applied to the inkjet recording head. However, the pump has a relatively complex configuration and requires a large installation space.
Devices that use the drive power of the bidirectional movement of the carriage to supply ink in order to simplify and reduce the size of the pump are also known from the literature. See, for example, Japanese Unexamined Patent Appl. Pub. JP-A-2007-160639. The ink supply device taught in JP-A-2007-160639 has a carriage that moves bidirectionally, an ink cartridge that stores ink to be supplied to an inkjet recording head disposed on the carriage, an ink holding unit that holds the ink consumed during printing by the inkjet recording head, and an ink pump unit. The ink pump unit is compressed and supplies ink to the ink holding unit as a result of the carriage moving to a specified position, and expands and draws ink from the ink cartridge as a result of the carriage moving to a position separated from the specified position. The ink holding unit is used as a buffer for storing the ink delivered from the ink pump unit, and thus tends to increase device size and cost.
In light of the above, it would be desirable to have improved fluid supply devices and printing devices with reduced cost and/or complexity. It would also be desirable to have methods for cleaning such fluid supply devices and printing devices in an economical manner.